The Senate is the upper house of the Nigeria's bicameral legislature, the National Assembly of Nigeria. The National Assembly (popularly referred to as NASS) is the nation's highest legislature, whose power to make laws is summarized in chapter one, section four of the 1999 Nigerian Constitution. It consists of 109 senators: the 36 states are each divided in 3 senatorial districts each electing one senator; the Federal Capital Territory elects only one senator. [1][2]

Bills may be introduced in any chamber of the National Assembly. However, the Nigerian constitution provides that money bills (Revenue and Appropriation bills) must originate in the House of Representatives, although the approval of both the Senate and the House of Representatives is required for any bill, including money bills, to become law. [6]

The constitution provides several unique functions for the Senate that form its ability to "check and balance" other elements of the Federal Government of Nigeria. [7][8] These include the requirement that the Senate may advise and must consent to some of the President's government appointments; also the Senate must consent to all treaties with foreign governments and it tries all impeachments.

The "Majority party" is the party that either has a majority of seats or can form a coalition or caucus with a majority of seats; if two or more parties are tied the Senate President's affiliation determines which party becomes the majority party. The second largest party is the Minority party.

A group of 15 senators of Nigeria’s ruling party defected to the main opposition group underscoring rising political tensions thereby making the All Progressive Congress lose her majority stake, although Senate President Bukola Saraki was not among initially, but he finally decamped to the people’s democratic party on Tuesday 31st July 2018. [10][11] In August 2018, Senator Akpabio resigned as the Senate Minority Leader while joining the long list of Legislative defectors by joining the ruling APC. [12]